VETPREP

Question 1

What does cyanosis generally indicate?

Answer 1

Hypoxemia -PaO2 of < 50 mm Hg

Question 2

This 2 year-old female spayed Siamese cat presents for further evaluation of the masses seen in the image. The patient was recently rescued and there is no other history available. On physical examination, there are no overt abnormalities appreciated other than the masses visualized. A fine needle aspirate is performed and consistent with a mast cell tumor. Given the breed, the histiocytic subtype is suspected. Which of the following is the most appropriate treatment plan if the owners don’t have unlimited funds?

Answer 2

Monitor as the lesions will most likely spontaneously regress

Question 3

A 7-year old female spayed Cocker Spaniel presents for an inflamed and buphthalmic left eye. She has a history of bilateral cataracts but can still see relatively well. Intraocular pressures were taken and the left eye was found to be high, while the right eye was within normal limits. What is the most likely cause for the increased intraocular pressure in the left eye?

Answer 3

Inherited glaucoma
- Cocker Spaniels are predisposed to developing eye problems such as cataracts, distichiasis, retinal abnormalities, and primary glaucoma.

Question 4

Which of the following tests used to test a population of cats will yield the most false negatives?

Answer 4

Sensitivity 65%, Specificity 95%

The sensitivity determines the number of false negatives because sensitivity looks at the animals that do have the disease of interest and is the percentage of them that will test positive. If 65% test positive, that means 65% are true positive and 35% are false negative. Specificity defines the number of true negatives and false positives.

Question 5

You are examining a flock of chickens that has recently had a 10-20% drop in egg production. You note that chickens are displaying signs of varying severity including watery eyes, nasal discharge, dyspnea with extension of the neck during inspiration, coughing of mucus and blood, and decreased food intake. There has been low mortality from this condition and you perform a necropsy on a deceased chicken and find caseous exudate and blood in the trachea. You suspect that this may be an outbreak of infectious laryngotracheitis. Which of these findings would confirm your diagnosis?

Answer 5

Intranuclear inclusion bodies in tracheal epithelium

Infectious laryngotracheitis (ILT) is caused by a herpesvirus. Intranuclear inclusion bodies in the tracheal epithelium help distinguish this condition from the diphtheritic form of fowlpox. Fowlpox virus produces intracytoplasmic inclusions. Liver necrosis with large, granular basophilic intracytoplasmic inclusions is consistent with avian chlamydiosis.

Question 6

Horses infected with this parasite may be predisposed to thrombosis of the cranial mesenteric artery.

Answer 6

Strongylus vulgaris

S. vulgaris undergoes extensive migration after being ingested as an infective larva. They leave the intestinal tract and travel around in the cranial mesenteric artery and its branches. S. equinus and S. edentatus also migrate throughout the body and may be found in the liver, pancreas, and perirenal regions. However, these parasites are not as likely to cause thrombosis of the cranial mesenteric artery. Trichostrongylus axei is usually only a problem when horses are in pastures with ruminants as this parasite is usually found in ruminants. The larvae of T. axei will penetrate the mucosa and cause ulceration, thickening of the mucosa, and a chronic gastritis. Triodontophorus tenuicollis is a small strongyle and does not migrate outside of the intestines. This particular parasite is known for being able to cause ulceration of the colon.

Question 7

A valuable horse suddenly developed severe intractable diarrhea and fever 5 days ago. The owner has been giving it oral electrolytes free choice in the water, and offering it hay, grain, and green grass. It is brought to your clinic on a normal warm summer day looking thin, dehydrated, weak, and anorectic (see photo). You do a physical exam and find T=102F (38.9 C), HR=56, RR=24, with somewhat purplish oral mucous membranes. The urine is normal but has a small volume and looks concentrated. You run a PCV (45%), WBC count (normal at 7000/microliter) and total protein (TP). The TP is low at 3.5 gm/dL and the albumin is 1.4 gm/dL indicating a protein-losing enteropathy. Of the following, what is the best treatment for the low plasma proteins in this horse?

Answer 7

IV plasma

The damaged bowel is leaking albumin out into the gut lumen, and the horse may develop other problems such as edema and poor healing ability if the protein levels are not boosted. The best way to do that in an animal with GI disease is by the IV route. Whole blood may raise the PCV to a level where sludging and circulatory problems develop in an already dehydrated horse. Another option to consider if plasma is not readily available is the use of synthetic colloidal solutions such as hetastarch.

Question 8

Several pigs have died at a farm. Clinical signs included star gazing, blindness, seizures, ataxia, nystagmus, and head pressing. Histologic examination of the brain demonstrates perivascular infiltration of eosinophils. What is the most likely diagnosis?

Answer 8

Salt poisoning

In pigs, observation of perivascular infiltration of eosinophils in the brain is a reliable indicator of salt poisoning. Additionally, the clinical signs are consistent with this diagnosis. Salmonella would not have produced the same histologic lesions, and you would expect diarrhea. Rabies is always on the differential list, but the histologic findings are not consistent with rabies. Do you recall the diagnostic lesion for rabies? Yes, it’s negri bodies. Vitamin A deficiency does not cause perivascular eosinophilic infiltration either.

Question 9

A horse presents for several days of lethargy, anorexia, and bleeding from its gums. Its prothrombin time is 20 seconds, and its partial thromboplastin time is 102 seconds. Its platelet count is 48,750/uL. Its antithrombin III activity is decreased as well. What is going on in this horse?

Answer 9

Disseminated intravascular coagulation (DIC)

DIC can be defined by having elevated PT/PTT, thrombocytopenia, and positive D dimer (a type of fibrin degradation product). Another parameter to evaluate is the fibrinogen concentration. Fibrinogen may be low in other species during DIC but is not commonly observed in horses. Usually two of these findings are enough to diagnose DIC. Antithrombin III activity is often decreased.

Coagulopathies are not uncommon in horses with infections, diseases such as severe colitis, pleuropneumonia, or strangulating intestinal lesions. DIC is a more severe coagulopathy in which both thrombosis and hemorrhage are occurring.

Question 10

A fluffed cockatiel with a recent history of anorexia and dyspnea presents to your clinic. You place the bird in oxygen for approximately an hour and then perform a physical exam. On physical exam you note coelomic distention. Blood work shows a heterophilia, increased AST, CK, and fibrinogen. What is the most likely diagnosis?

Answer 10

Egg yolk peritonitis

Egg yolk peritonitis can be life-threatening. Clinical signs include anorexia, fluffed feathers, coelomic distention, and dyspnea. Blood work findings are consistent with egg yolk peritonitis. If gout was the diagnosis, we would expect to see painful joints. We would not expect to see coelomic distention with aspergillosis. With egg binding you would not expect to see hyperfibrinogenemia. Additionally, cloacal straining could potentially be present. Treatment for egg yolk peritonitis involves antibiotic therapy, surgery, and anti-inflammatories.

Question 11

Calcium homeostasis is extremely important in lactating animals and is controlled by two hormones, parathyroid hormone (PTH) and what other hormone?

Answer 11

Calcitonin

Calcitonin is produced by the C cells of the thyroid gland in response to high calcium levels in blood. Calcitonin increases renal calcium excretion and decreases osteoclastic activity (bone resorption). PTH does the opposite and also stimulates renal production of 1,25-dihydroxycholecalciferol. This form of vitamin D stimulates intestinal cells to increase Ca absorption.

Question 12

Which of the following agents is monitored by the National Poultry Improvement Plan because it is egg-transmitted and is characterized by swollen, mucus-filled infraorbital sinuses in turkeys (“infectious sinusitis”)?

Answer 12

Mycoplasma gallisepticum

In turkeys, these bacteria result in swollen infraorbital sinuses. It is currently monitored in breeder flocks by serum plate agglutination test.

Question 13

You examine a valuable beef bull that was recently purchased in Texas and taken to the mountains of Colorado. The pasture is a mountain meadow at 10,000 feet elevation. The bull has developed edema of the brisket and ventral thorax, submandibular edema, dyspnea and tachypnea. Rectal temperature is normal. The HR is 90, and heart sounds are clearly audible without murmurs. What is your diagnosis?

Answer 13

High mountain disease

The key to this question is the altitude mentioned in the question and accompanying clinical signs. Also called brisket disease and high altitude disease, this condition can be fatal and is brought on by elevations above 6000 feet. Hypoxic vasoconstriction (worse in some lines of cattle) causes pulmonary hypertension, which leads to cor pulmonale, which is secondary cardiac disease including right heart enlargement and failure.

Question 14

2-year old MN DSH has recently been treated for a urethral obstruction. He went home last week from the hospital on an acidifying canned diet for this condition. The owner reports he is passing urine in moderate amounts, but he is still straining frequently. You re-examine the cat and find that the bladder is empty on palpation and the wall feels a little thickened. You are confident that the cat has not re-blocked and the cat’s bloodwork shows normal electrolytes and renal values. Which of the following medications may help the cat with this problem?

Answer 14

Phenoxybenzamine

This cat is likely suffering from hypertonicity of urethral muscle, which was incited from the recent obstruction and urinary catheter. This can cause spasms, which makes urinating painful and not easily controlled. Phenoxybenzamine can be used in this case to reduce internal urethral sphincter tone such that the cat may urinate more easily.

Methocarbamol is a muscle relaxant but would not directly help spasms of the urethra.

Prednisolone is not used to help reduce inflammation or spasms in the urethra and may predispose the cat to contracting a urinary infection, especially while his bladder and urethra are compromised.

Phenylpropanolamine is used to treat urinary incontinence from urethral hypotonicity most often in dogs and would be contraindicated in this case.

Amitriptyline is an anti-depressant medication that has been implicated as part of a treatment plan for cats with cystitis, although benefit has never been proven. Because cats with cystitis can flare up during times of stress, the amitriyptyline has been thought to help prevent this. This medication would not work to stop spasms in the urethra.

Question 15

Which of the following is the treatment of choice for a Taenia infection in dogs?

Answer 15

Praziquantel

Pyrantel and ivermectin are not known to be effective against Taenia infections. Fenbendazole is effective against Taenia pisiformis, but not other subspecies of Taenia, making it a less desirable answer choice.

Question 16

A herd of pigs present for unthriftiness, slow growth, and occasional deaths. Some pigs show signs of posterior ataxia or paralysis. The farmer says his herd was previously infected with Stephanurus dentatus. Which of the following diagnostics is most appropriate to make the diagnosis of Stephanurus dentatus?

Answer 16

Urinalysis

Stephanurus dentatus is the kidney worm of pigs. The parasites are often in or near the kidneys, in the ureters, or in perirenal fat. Posterior ataxia or paralysis can occur due to larvae migrating along the spinal cord. Diagnosis is usually made on necropsy or by finding ova in the urine.

Question 17

A 6-month old domestic short hair cat presents for its first physical exam. Cardiac auscultation reveals a grade IV/VI holosystolic murmur on the right thorax. Thoracic radiographs were unremarkable and echocardiography showed a small turbulent jet flowing through the ventricular septum from the left ventricle to the right ventricle. Which of the following do you tell the owner?

Answer 17

The prognosis is very good with small ventricular septal defects and no treatment is needed

The prognosis of small VSDs is very good. Some will close by themselves within the first year of life. It is unlikely that a small VSD will cause any significant problems such as heart failure, though follow-up evaluation is warranted to monitor cardiac size and function. Large VSDs carry a guarded prognosis and require cardiac bypass for surgical correction or novel device closure via transcatheter techniques; neither of which are commonly employed in animals. Small VSDs cause a relatively more turbulent jet of blood through the small defect, causing a louder murmur than a large VSD.

Question 18

A 12-year old female spayed Himalayan cat presents to you for acute onset of left hind limb lameness after leaping off of the counter to the floor this morning. The cat is non-weight bearing and very painful around the left stifle. You take a radiograph (shown below). Which of the following conclusions can you make about the cat’s injury?

Answer 18

A pathologic fracture occurred when the cat jumped off of the counter

There is marked osteolysis of the proximal tibia with a pathologic fracture. This fracture will not heal with either rest or with rigid fixation due to the presence of underlying disease that resulted in the osteolysis. The most likely cause is a tumor of the bone. In cats, unlike dogs, many bone tumors do not have a high metastatic rate and do not necessarily require adjunct chemotherapy although histopathology would be needed to confirm the tumor type and grade.

Question 19

A 9-year old Quarter Horse mare is presented for hindlimb ataxia, dog sitting (see image) and intermittent dribbling of urine. Two other horses at the same facility have recently demonstrated similar signs to varying degrees. What is the most likely cause?

Answer 19

Equine Herpes Myeloencephalopathy (EHM)

The most likely cause is EHM, which is associated with vasculitis of the central nervous system and associated clinical signs. Neurologic signs are usually acute and are characterized by hindlimb ataxia, hypotonia of the tail/anus, and urinary incontinence. EPM could possibly cause similar signs but is not typically seen in multiple animals on the same farm. Wobbler Syndrome and EDM typically affect young horses.

Question 20

Which of these conditions is most likely to progress and cause cardiac tamponade in a dog?

Answer 20

Right atrial hemangiosarcoma

Cardiac tamponade comes from excessive accumulation of fluid in the pericardium resulting in an increased intrapericardial pressure impairing diastolic filling of the heart. Of the answer choices, right atrial hemangiosarcoma is the only one that results in pericardial effusion. Other causes include heart base tumors, right sided congestive heart failure, idiopathic pericardial hemorrhage, peritoneopericardial diaphragmatic hernia, infectious pericarditis, trauma, foreign body, coagulopathy, and hypoalbuminemia.

Question 21

Purpura hemorrhagica is an immune complex disease of horses that leads to urticaria, edema, petechia, ecchymoses, and vasculitis. What disease is it usually secondary to?

Answer 21

Streptococcus equi ssp. equi

Question 22

Gossypol toxicity in young ruminants can cause sudden death as result of a ___________.

Answer 22

Cardiomyopathy

Question 23

What is the most common tumor of the oral cavity in the dog, as seen in the photo?

Answer 23

Melanoma

Melanoma comprises about 1/3 of all oral tumors in dogs. Many oral melanomas may be amelanotic, as the one in the photograph appears to be. The second most common tumor is squamous cell carcinoma followed by fibrosarcoma and acanthomatous epulis.

Question 24

Fluoride toxicity at a young age in cattle may result in permanent damage to which of the following?

Answer 24

Teeth

Question 25

Two 9-year old female spayed Labrador retrievers presented for their next chemotherapy treatments. Both were diagnosed with multicentric lymphoma and have been receiving the CHOP protocol. One received doxorubicin (Adriamycin) and one received vincristine (Oncovin) today. Your technician informs you that both unfortunately had extravasations occur and wants to know what she should do. Which drug is a worse vesicant and what should be done to the injection site?

Answer 25

Doxorubicin. Cold compress to contain the spread of drug Intravenous chemotherapy drugs can cause severe tissue necrosis (doxorubicin) or irritation (vincristine) if extravasation occurs. Treatment for both should begin immediately. In both cases, the catheter should be left in place and as much of the drug should be aspirated as possible. Treatment for doxorubicin extravasation involves cold compressing the site to promote vasoconstriction, however perivascular necrosis may still occur and may progress days to weeks later. In severe cases involving doxorubicin, debridement or limb amputation may be needed. Vincristine extravasation should be treated with warm compresses to disperse the drug and enhance systemic absorption. Extravasation should be prevented through patient restraint training, use of catheters that have been placed on the first stick, and careful monitoring during administration. The peripheral veins should be avoided for blood draws if possible on all patients receiving chemotherapy.

Question 26

What is the appropriate treatment for a dermatitis known to be caused by a food allergy in a dog?

Answer 26

Feeding a diet with novel protein and carbohydrate sources or a hydrolyzed diet.

Question 27

You examine a 6-year old Quarter Horse gelding for a complaint of lameness. He has a short-strided stilted gait in the forelimbs, is more painful on a hard surface than on a soft grass surface, and head nods when led in a tight circle at the trot in either direction. The hoof tester elicits pain in the posterior third of the foot on both forefeet. The hoof appears normal except that it has narrow heels. A block of the palmar digital nerves seems to result in loss of hoof tester sensitivity and an improved gait. What condition is associated with these clinical findings?

Answer 27

Navicular disease Palmar foot pain can be the result of pain from any number of structures including the navicular bone, navicular suspensory or deep digital flexor tendon, navicular bursa, or several other heel areas. Navicular disease is a term used for pain associated with any of these structures.

Question 28

A recently freshened 4-year old Guernsey with a body condition score of 4/5 presents for decreased milk production, anorexia, and depression. On physical exam, she has a mild fever and is ketotic. No pings were auscultated during the physical exam and a rectal exam was unremarkable. What is the most likely diagnosis?

Answer 28

Fatty liver syndrome The correct answer is fatty liver syndrome. Fat cows are more predisposed to fatty-liver syndrome when they encounter a negative energy balance. Shortly after parturition, their energy needs increase dramatically with lactation. Clinical signs are vague so you must be able to reach the answer by paying attention to the signalment. Further, an RDA will present with much more systemic signs and you will be able to hear a ping. PA toxicity and oleander toxicity are possible but less likely given the signalment and clinical signs. Remember, oleander is cardiotoxic and causes arrhythmias and PAs will cause chronic damage to the liver.

Question 29

Which of the following best describes Type III hypersensitivity?

Answer 29

An immune complex hypersensitivity involving the interaction of circulating antigen-antibody complexes in blood vessel walls causing neutrophil emigration and tissue damage

Question 30

A backyard hen presents with a history of being previously active followed by sudden death with no premonitory signs. Gross examination reveals an obese hen with pale, friable liver and broad blood clots attached to the liver capsule and extending into the abdomen. There is no evidence of external trauma. The most likely diagnosis is:

Answer 30

Fatty liver/hemorrhagic syndrome

Question 31

A group of swine have pyrexia, inappetence, dyspnea, swollen painful joints and lameness. You have tentatively diagnosed Glasser`s Disease caused by Haemophilus parasuis. Which of the following treatments should you use?

Answer 31

Ceftiofur The organism is usually susceptible to ampicillin, ceftiofur, enrofloxacin, florphenicol, spectinomycin, tetracyclines, tiamulin, tilmicosin, and potentiated sulfas. Today, many strains of Haemophilus parasuis are resistant to penicillin (penicillin used to be the drug of choice) and all other choices are not permitted for use in food animals in the USA.

Question 32

Which of the following is a common cause for diarrhea in growing and finishing pigs?

Answer 32

Salmonella

Question 33

Several 6 month-old calves have died on a large ranch, and you have performed a post-mortem exam and diagnosed blackleg (see image). The owner, who has never vaccinated his calves, would like your recommendations for prevention.

Answer 33

Vaccinate all calves at 4 to 6 months of age with killed vaccine containing Clostridium septicum and several other common Clostridial organisms.

Question 34

A 1-year-old male neutered cat is transferred to you in the morning after seeing an emergency service for electrical cord bite trauma. You anesthetize the cat to address numerous oral burns and ulcers and note frothy pink fluid accumulating in the endotracheal tube (see image). What is the likely cause of this?

Answer 34

Non-cardiogenic pulmonary edema Electrical cord trauma commonly causes burns and ulcerations of the mouth, lips, and tongue. Due to the effect of electrical current on capillaries, non-cardiogenic pulmonary edema is an important complication to expect and monitor for. Although electrical cord bites can cause cardiac arrest, congestive heart failure would not be an expected complication.

Question 35

A 3-month old female Portuguese Water Dog presents to you for immunizations. The dog appears healthy on physical exam with no clinical abnormalities. The owner does not plan to breed the dog, and you advise her that ovariohysterectomy can decrease the risk of certain diseases in the future. When should dogs be spayed in order to get the maximum reduction in the risk of mammary cancer?

Answer 35

Before the first estrus Development of mammary tumors in the dog is hormone-dependent. As such, ovariohysterectomy before a heat cycle prevents the hormonal effects on the mammary glands that predispose them to developing tumors. Dogs spayed prior to an estrus are 0.05% times as likely to develop a mammary tumor as an intact dog. That risk rises to 8% and 26% after one and two heats respectively with no decrease in risk if they are spayed subsequent to a third heat.

Question 36

A 10-year old female spayed Siamese cat presents for a new lump the owner found a month ago. She was spayed last year before she was adopted from the shelter. The owner states that the lump has grown over the last month, and it doesn't seem to bother the cat. On exam, the 2 cm lump is located on the left 2nd mammary gland, and no other lumps are noted. The lump is freely moveable, and chest radiographs are clear. What is the chance that this tumor is malignant?

Answer 36

85% 70-90% of all feline mammary tumors are malignant. Spaying a cat before 6 months of age reduces the risk for mammary tumors by 7 fold. The statistics for dogs is a 50:50 chance of malignancy for a single mammary mass.

Question 37

This ECG recording (bottom recording) is from a 10-year old miniature poodle with a history of heart disease that is untreated. She presented for a 3-day history of diarrhea and decreased appetite. On physical examination you auscult a grade III/VI heart murmur and clear lung sounds. There are no obvious pulse deficits palpated. What is the appropriate treatment for this arrhythmia?

Answer 37

No anti-arrhythmic therapy is necessary at this time

Question 38

An 8 week old Beefmaster calf presents with a 2 day history of rapid and labored respiration, depression, salivation, nasal and ocular discharge, and a "honking" cough. On physical exam, there are no signs of sepsis, but the calf is tachypneic, dyspneic and febrile. Crackles are audible throughout the lung fields. What is your top differential?

Answer 38

Bovine respiratory syncytial virus The key to being able to make this your top differential is noting that the calf has a "honking" cough, dyspnea, and tachypnea, that the calf is not septic. Pulmonary lesions include severe edema and emphysema. Treatment is usually supportive and antibiotics are given to protect from secondary bacterial infection. Mannheimia hemolytica is the main culprit in shipping fever, and Haemophilus pleuropneumoniae is an occasional cause of shipping fever in cattle. Pasteurella multocida can be a secondary invader in any bovine pneumonia. P multocida also causes the most economic loss in swine with atrophic rhinitis.

Question 39

What is the definitive host of Sarcocystis cruzi?

Answer 39

Dog The ruminant is an intermediate host. Sarcocystis hirsuta involves the cat as the definitive host. Primates are the definitive host for Sarcocystis hominis. The life cycle involves a carnivore eating an infected cow which has cysts in the muscle. Then the cyst eventually forms sporocysts which are shed in feces and subsequently eaten by more cows. The sporocysts then hatch and penetrate artery walls and hang out in the endothelium to develop into sporozoites and eventually become merozoites at which time they invade muscle and encyst as sarcocysts. It takes about 10 weeks for the entire maturation process to occur. Clinical signs are non-specific such as fever, anorexia, salivation, weakness, muscle fasciculations, and weight loss. Diagnosis is likely to be at necropsy; so, prevent carnivore feces from contaminating the area. The definitive host of Sarcocystis hirsuta is the cat and for Sarcocystis hominis, it is the human.

Question 40

Which of the following is not a possible sequela of calcium, phosphorus, and vitamin D3 imbalance in a pet bird?

Answer 40

Proventricular dilatation

Question 41

You are routinely checking purebred Holstein calves for failure of passive transfer (FPT) at 48 to 60 hours of age and discover one with a very low serum IgG. The calf weighs 40 Kg. Which of the following is the most effective course of action to correct the problem and maintain a healthy calf?

Answer 41

Transfuse with 1 to 2 L bovine plasma

Question 42

The owner of a new beef ranch on poor volcanic soil asks you to evaluate 2 steers. They are representative of an ongoing herd problem of chronic diarrhea and respiratory disease that is unresponsive to antibiotic treatment. On physical exam, you notice achromotrichia, ill thrift, and a temperature of 103F (39.4 C) in both steers. You perform a transtracheal wash in one of the steers and it comes back positive for Pasteurella multocida. What is your diagnosis?

Answer 42

Copper deficiency The giveaway is achromotrichia or loss of hair color. Dilution of the coat color is due to dysfunction of tyrosinase which converts L-tyrosine to melanin. In addition, copper deficient animals will have spontaneous fractures, secondary respiratory disease, diarrhea, ill thrift, decreased immunity, anemia, and poor reproduction. Selenium deficiency and BVD are actually pretty good differentials and if achromotrichia was not present either of those two are reasonable choices. Molybdenum deficiency would not result in achromotrichia. On the other hand, if there had been excess molybdenum, then the Cu:Mo ratio would be off and copper deficiency could be observed.

Question 43

A relative calls you to ask how she can stop her 4-year old Cockapoo from begging for food at the table. You advise her not to pay any attention to the dog when it is showing this behavior. What behavioral principle is this?

Answer 43

Operant conditioning is the use of consequences to modify the occurrence of a behavior. In this case, the dog has learned that begging behavior has previously been met with positive consequences (i.e. being fed or receiving attention). Extinction is the lack of any consequence following a behavior. When a behavior is inconsequential, producing neither favorable nor unfavorable consequences, it will occur with less frequency. When a previously reinforced behavior is no longer reinforced with either positive or negative reinforcement, it leads to a decline in the response. Negative reinforcement occurs when a behavior is followed by the removal of an aversive stimulus thereby increasing that behavior's frequency. An example is a loud noise continuously sounding until a lever is pressed, upon which the loud noise is removed. This will encourage the behavior of pressing the lever. Negative punishment, also called punishment by contingent withdrawal, occurs when a behavior is followed by the removal of a favorable stimulus, such as taking away a child's toy following an undesired behavior, resulting in a decrease in that behavior. Avoidance learning is when a behavior results in the cessation of an aversive stimulus. For example, holding your ears to shield them from a loud, high-pitched sound helps avoid the aversive stimulation of that obnoxious sound. Noncontingent reinforcement is the delivery of reinforcing stimuli regardless of the animal's behavior. This causes that behavior to decrease because it is not required in order to receive the reward.

Question 44

Which of the following is required for chinchilla health?

Answer 44

Dust bath

Question 45

The goose shown in the image below was found weak on the shore of a local pond where oil had been dumped. The goose was covered in oil, dehydrated and weak but responsive. Which of the following is an important acute clinical effect of oil on affected birds?

Answer 45

Disruption of function of the plumage Feathers serve a critical waterproofing and insulatory function which is disrupted by oil and can rapidly result in hypothermia. Other concerns for oiled birds include GI irritation from ingestion of oil during preening, hemolytic anemia, and pneumonia due to inhalation of oil. Treatments include heat, supportive care, and activated charcoal. Once stabilized, frequent high pressure, warm, mild detergent baths and clean warm water rinses until water beads freely off of the feathers is important. Birds should be placed in warm air flow until dry and they should be maintained on self-skimming ponds for several days after washing to ensure full waterproofing.

Question 46

A 2-year-old neutered male greyhound presents for crusting along his ear pinnae and elbows. The owner also explains that the dog is intensely pruritic. The dog mainly lives indoors but is also let outside into the backyard. The owner lives on a large rural property that is heavily wooded. You perform cytology, which returns negative for bacteria and yeast. You are highly suspicious of Sarcoptes. Which of the following would be most useful to help in your diagnosis of Sarcoptic mange?

Answer 46

Pinnal-pedal reflex, clinical signs, superficial skin scrape A superficial skin scrape is most useful. A deep skin scrape is used for Demodex mites, which reside in the hair follicles. Superficial skin scraping is indicated for Sarcoptic mange, since this mite lives in the stratum corneum. Pinnal-pedal reflex can be positive in 70% of Sarcoptic mange infestation but can also be positive in any dog with pruritus. Clinical signs are helpful because Sarcoptes typically infects the non-haired portions of the skin such as the ear pinnae, elbows, hocks, and ventral abdomen. If the mite is not found on skin scraping and you have clinical signs indicative of Sarcoptes then a therapeutic trial is warranted. Keep in mind that in most cases you will not be able to find the mite. A trichogram would not be indicated. This method can be used to diagnose dermatophytosis and sometimes Demodex. Histopathology will reveal a perivascular dermatitis that is non-specific. Rarely are the mites found on histopathology.

Question 47

Which of these is most likely to cause Theiler's disease?

Answer 47

Tetanus antitoxin

Question 48

You are a practicing veterinarian in sunny California when a 5-year old female spayed Doberman arrives at your clinic with anorexia, lethargy, depression, and weight loss. On physical exam you notice several nodular and draining skin lesions. There is lymphadenopathy, and you detect a cough. Further examination reveals uveitis. You question the owner and he mentions that he and his dog are originally from the Ohio River valley. You perform cytology on fine needle aspirates that you obtained from the skin nodules and enlarged lymph nodes. What organism do you expect to find?

Answer 48

Blastomyces dermatitidis You can come to this diagnosis by thinking about the clinical findings and travel history, which are both characteristic for blastomycosis. On cytology you can expect to see a 5-20 micrometer diameter thick, refractile, double-contoured cell wall, and broad-based budding organism. Transmission is a result of spores inhaled from the environment which form yeast in the lungs and then disseminate through the blood and lymphatics. Itraconazole is usually the drug of choice for uncomplicated disease. Histoplasmosis usually occurs in the Ohio, Mississippi, and Missouri river valleys, but skin and ocular lesions occur uncommonly. Usually, you will see GI involvement, especially large bowel. Usually, with histoplasmosis you will see large numbers of small round bodies with a basophilic center in mononuclear phagocytes from your sample.

Question 49

A 4-year old female Abyssinian cat presents to you with a complaint of weight loss and polyuria and polydipsia. On exam, the cat appears slightly underweight, but otherwise there are no significant findings. You perform a complete blood count, chemistry panel, and urinalysis. The cat has a hematocrit of 27%, white blood cell count of 4,500/uL, and 350,000 platelets/uL. The chemistry panel shows Ca=10.5 mg/dL, P=3.5 mg/dL, bilirubin=0.l mg/dL, albumin=2.7 g/dL, globulin=2.7 g/dL, ALT=50 IU/L, glucose=104 mg/dL, BUN=59 mg/dL, Creatinine=3.8 mg/dL, and cholesterol= 120 mg/dL. Urinalysis shows a specific gravity of 1.010 with no bilirubin, glucose, or ketones detected and trace protein. You measure systolic blood pressure of 160 mmHg. Abdominal ultrasound shows subjectively small kidneys with increased renal echogenicity. Due to the cat's young age and breed, you suspect an underlying hereditary condition to the cat's renal disease. The owner reports that the breeder she obtained the cat from promised her that the line was free of any genetic disorders. You explain to the owner that a kidney biopsy may be the only way to rule in or out this hereditary disease. What specific test should you recommend on the biopsy sample?

Answer 49

Congo red staining for amyloid Of the many forms of amyloidosis, reactive (secondary) systemic amyloidosis is seen in the cat as a familial disorder of the Abyssinian, Siamese, and Oriental Shorthair. Amyloid deposition occurs most frequently in the kidney (Abyssinian) and liver (Siamese and Oriental Shorthair) although other sites can be affected. Clinical signs in the Abyssinian are typically those of chronic renal failure. Hypertension may be secondary to glomerulotublar disease. Renal or liver biopsies can confirm the diagnosis but are often unnecessary due to the risk of hemorrhage, and there may only be minimal change to therapeutic decision making. Congo red staining of biopsy samples should be requested because hematoxylin and eosin staining do not always show amyloid deposits. Therapy consists of general management of the renal failure, proteinuria, hepatopathy, and hypertension if they exist. There are reports of using dimethyl sulfoxide (DMSO) or colchicine for these cats as well. Obviously, this cat should not be bred.

Question 50

A new client from North Carolina comes to your practice to bring in her 5 year-old male neutered hound dog, Bart, and her 10 year-old male neutered domestic short hair, Spaz, for examination. Spaz has been doing fine and just needs his yearly preventative care, but Bart has been lethargic with weight loss and intermittent lameness. On physical exam, you note that the dog has a thin body condition score of 3/9, generalized lymphadenopathy and a fever of 104.2 F (40.1 C). The cat seems completely normal and healthy enough for vaccinations. During your attempt to vaccinate Spaz, he gets very agitated and scratches the owner on the arm. She notes that Spaz is kind of a difficult cat and that he has scratched her many times before; after one incident, the owner needed antibiotics for an infection that spread to her armpit from one of the cat's scratches. She mentions that she probably should have told you that Spaz can be difficult prior to the exam. Given the dog's (and owner's) clinical signs and travel history, what disease might you suspect at this time?

Answer 50

Bartonella Bartonella henselae is the bacterium that causes cat-scratch disease. In cat-scratch disease, the owner is infected with the bacteria from flea feces when the cat bites or scratches the owner. Commonly, the bacteria cause fever, malaise, weight loss and lymphadenopathy. Often, cats show no clinical signs. Dogs can be exposed via tick or flea vector and show signs similar to humans, including possible endocarditis. With the dog and cat being from a southern state, both animals were at risk of exposure from Bartonella species.

Question 51

A 10 year old female spayed German shepherd dog presents for collapse and difficulty breathing. Your physical exam shows pale mucous membranes, a fluid wave in the abdomen and a splenic mass. Aspiration of the abdominal fluid shows hemorrhagic effusion that does not clot. Which of the following is commonly found with your presumed diagnosis?

Answer 51

Disseminated intravascular coagulation The presumed diagnosis based on the given signalment, physical findings, and diagnostics is splenic hemangiosarcoma, which is often associated with DIC.

Question 52

What species are primarily affected by both internal and external caseous lymphadenitis, a manifestation of Corynebacterium pseudotuberculosis?

Answer 52

Sheep and goats The cutaneous abscesses caused by this organism also affect cattle. Horses experience pectoral abscesses, internal abscesses, and other sites, as well ulcerative lymphangitis (also caused by C. pseudotuberculosis) of the limbs.

Question 53

Which of the following is not a management measure for controlling swine colibacillosis?

Answer 53

Commingling pigs of different ages

Question 54

How is cryptosporidiosis treated in reptiles?

Answer 54

There is no effective treatment The correct answer is there is no effective treatment. Clinical signs of cryptosporidiosis in reptiles include regurgitation, weight loss, and debilitation. The organism causes thickening of the gastrointestinal mucosa and loss of motility. Diagnosis is made by acid-fast staining of fresh feces or regurgitated food. Since there is no effective treatment euthanasia is often recommended.

Question 55

A 3-year old male castrated Labrador Retriever presents for severe hemorrhagic enteritis, lethargy, and anorexia. The dog has a history of going fishing with the owner about one week before the onset of the clinical signs. The physical exam reveals generalized lymphadenopathy. Which of the following is the most likely etiologic agent causing these clinical signs?

Answer 55

Neorickettsia helminthoeca This dog most likely has salmon poisoning disease. The etiologic agent of the disease is the rickettsia, Neorickettsia helminthoeca, which is vectored by the intestinal fluke, Nanophyetus salmincola. Dogs get the disease by eating salmonid fish infected with the cercaria of the fluke, which harbor the rickettsia. Clinical signs along with finding fluke eggs in the feces of the dog is usually enough to make the diagnosis. Paragonimus kellicotti is a lung fluke of the dog.

Question 56

You are treating a 5-year-old male neutered cat that has diabetes mellitus. He is eating well at home and is no longer polyuric and polydipsic. You are treating him with 2U PZI insulin twice daily. His body weight is stable compared to his last visit. He ate a normal amount of food this morning and received his insulin before coming to see you. His blood glucose on presentation, 1 hour after receiving insulin, was 301 mg/dL (normal is 60-125mg/dL). You evaluate a blood glucose curve with readings every 2 hours after the initial reading, and your results are: 274 mg/dL, 233 mg/dL, 130 mg/dL, 101 mg/dL, 248 mg/dL. What would you recommend to this cat's owner?

Answer 56

Continue 2U PZI BID and recheck BG curve in 2 months

Question 57

An iguana is presenting for a change in behavior described as hyperactivity and irritability. The iguana has also recently stopped eating and seems to have an enlarged abdomen. What is the most likely diagnosis?

Answer 57

Gravid female The clinical signs described are typical for a gravid female. They are most likely to present from November to June. On physical exam you can typically feel the lumps in the abdomen which are the large eggs. Intervention in the form of an ovariohysterectomy is performed if attempts at inducing oviposition fail.

Question 58

Which of the following endocrine imbalances does not commonly cause a dermatosis in dogs?

Answer 58

Central diabetes insipidus Males with Sertoli cell tumors may develop bilateral alopecia with occasional pruritus and papular eruptions. Hypothyroid dogs often develop alopecia, seborrhea, and pyoderma. Hyperadrenocorticism patients commonly develop hyperpigmentation, alopecia, calcinosis cutis, seborrhea, and pyoderma.

Question 59

In mid-autumn you attend a group of 64 housed beef cattle aged 9-12 months, purchased from numerous markets over the previous 3 weeks. Frequent coughing has been heard in the group over the past week. The farmer has selected two inappetant animals with purulent ocular and nasal discharges for veterinary examination. Clinical examination reveals pyrexia 105.4 and 106.0F (40.8 to 41.1 C). The respiratory rate is increased and auscultation of the chest reveals referred upper respiratory tract noise. Visual inspection of the remainder of the group reveals a number of cattle with mucopurulent ocular and nasal discharges and tachypnea as well as several cows who have a swollen vulva with erosions and ulcers. Six animals are selected and examined, all of which have a rectal temperature > 105 F (40.6 C). Which of the following recommendations is best?

Answer 59

Vaccinate all cattle with intranasal vaccine against the virus and treat sick animals with intramuscular procaine penicillin for 3 days

Question 60

What is the significance of low milk progesterone levels on day 0 of estrous and high on day 21 and 24 in a cow?

Answer 60

Likely pregnant The correct answer is that the cow is likely to be pregnant. If the progesterone levels were low on days 0, 21, and 24 of estrous, it is almost certain she is not pregnant. High progesterone levels throughout may indicate that she has been pregnant or that she has a persistent corpus luteum. In this scenario, with low levels initially at day 0 but high at day 21 and 24, this cow should be pregnant.

Question 61

A 2-year old male castrated mixed breed dog presents for an altered gait after being hit by a car. On physical exam, the thoracic limbs had decreased biceps and triceps reflexes and decreased muscle tone. The pelvic limbs had hyper-reflexive patellar and gastrocnemius reflexes and increased muscle tone. Where is the spinal cord lesion?

Answer 61

C6-T2

Question 62

A 5-year-old female spayed Jack Russell Terrier arrives at your clinic with coughing and nasal discharge of 2 days duration. The dog has a history of being kenneled last week while the owners were on vacation. She has been lethargic since she got home and did not eat her breakfast this morning. Her temperature is 102.8, heart rate 140 and respiratory rate 30. Which of the following is your top differential?

Answer 62

Bordetella bronchiseptica

Question 63

A 5-day old foal presents with weakness, rapid breathing, and fever. Which of these methods would be the most useful test for rapid detection of failure of passive transfer?

Answer 63

ELISA (SNAP) test

Question 64

Which type of urolith occurs most commonly in western U.S. range cattle grazing mature grasses as shown in the photo? Image courtesy of David Van Metre

Answer 64

Silicate

Question 65

A 3-year old male castrated cat presents to your clinic for inappetence and depression of 3 days duration. On physical exam, the cat is febrile with a temperature of 103.6F (39.8 C) and is 8% dehydrated. ``` Complete blood count shows: Hematocrit - 36% (30-45 %) White blood cell count- 25,678/ul (5,500-19,500/ul) Neutrophils- 21,678/ul (2,500-12,500/ul) Lymphocytes- 3,300/ul (1,500-7,000/ul) Monocytes- 200/ul (0-900/ul) Eosinophils- 500/ul (0-800/ul) Platelets- 210,000/ul (300,000-800,000/ul) ``` ``` Serum chemistry shows: Creatinine- 1.8 mg/dl (0.9-2.2 mg/dl) Blood urea nitrogen (BUN)- 30 mg/dl (19-34 mg/dl) Glucose- 70 mg/dl (60-120 mg/dl) Albumin= 3.2 g/dl (2.8-3.9 g/dl) Globulin= 2.8 g/dl (2.6-5.1 g/dl) ALP- 95 IU/L (0-45 IU/L) ALT- 349 IU/L (25-97 IU/L) GGT- 12 IU/L (0-6 IU/L) Total bilirubin- 1.1 mg/dl (0-0.1 mg/dl) ``` You perform an abdominal ultrasound and find that the liver appears subjectively enlarged. The echogenicity of the liver and spleen are normal. The gall bladder appears mildly enlarged; no choleliths are seen. The pancreas does not appear sonographically enlarged or abnormal. The kidneys and the remainder of the abdomen appear unremarkable. You perform an ultrasound guided liver biopsw y. Histopathology indicates fibrosis associated with portal triads, bile duct proliferation, and centrilobular accumulation of bile with casts in canalicular areas. With treatment, what is the cat's prognosis?

Answer 65

50% chance of long term survival, 50% chance of dying within 3 month The case described is very consistent with acute cholangiohepatitis. This condition is usually seen in younger cats (mean age 3-3.5 years) and is more common in males than females. This is in contrast to chronic cholangiohepatitis which occurs in older cats (mean age 9 years). Acute cholangiohepatitis patients are more likely to be depressed, dehydrated and febrile. Bloodwork in cholangiohepatitis often shows a neutrophilia with or without a left shift. Mild increases in bilirubin and ALP are common, often with more severe elevations of ALT. The sonographic and biopsy findings are also consistent with the diagnosis of acute cholangiohepatitis and make other differentials such as hepatic lipidosis or lymphocytic portal hepatitis less likely. Treatment of choice for this disease includes antibiotics with aerobic and anaerobic coverage that are excreted unchanged in the bile. Examples of antibiotics excreted unchanged in the bile include tetracyclines, ampicillin, amoxicillin, erythromycin, chloramphenicol, and metronidazole. Usually erythromycin, tetracycline, and choloramphenicol are not the first choices unless they are indicated based on culture and sensitivity because erythromycin is not effective against gram negative bacteria, tetracycline is hepatotoxic, and chloramphenicol may cause anorexia. Ampicillin or amoxicillin with clavulanic acid are good choices and metronidazole may be used to expand the anaerobic coverage. Ursodeoxycholic acid (Actigall) is useful in all types of inflammatory liver disease because of its anti-inflammatory and anti-fibrotic properties on the liver. It also increases fluidity of biliary secretions. With treatment, it is thought that the response of acute and chronic cholangiohepatitis cases is similar with about half of animals dying or being euthanized within 90 days and half of them having prolonged survival.

Question 66

What is the most likely complication associated with the post-anesthetic recovery of the dog in the photograph receiving Clotrimazole?

Answer 66

Laryngeal inflammation The correct answer is laryngeal inflammation. Seizure is a possible sequela if the cribriform plate is compromised. If this were the case, the complication would likely be fatal. With severe swelling, the administration of corticosteroids and re-intubation is indicated. Sometimes these dogs may need to be intubated for days.

Question 67

What are the most common etiological agents of contagious footrot in sheep?

Answer 67

Dichelobacter nodosus and Fusobacterium necrophorum

Question 68

A 2-year old Terrier mix presents for an alopecic, raised nodule on its head. The owner describes previous similar lesions that have ulcerated and regressed over time. What is your most likely diagnosis?

Answer 68

Cutaneous histiocytoma

Question 69

What is the most common respiratory disease of barn raised dairy calves 1-6 months of age in the United States?

Answer 69

Enzootic pneumonia

Question 70

A 4-year old female spayed tabby cat presents for labored breathing over the last 2 weeks. You suspect pleural effusion based on exam, and thoracocentesis produces a milky fluid (see image). The cat's temperature is 102.0 F (38.9 C) and bloodwork is unremarkable. You suspect the fluid to be chyle. How would you confirm this suspicion?

Answer 70

Measure triglycerides on the effusion as compared to peripheral blood Chyle has a high triglyceride content and if the effusion has a higher triglyceride value than the concurrent peripheral blood sample, this is most diagnostic. Other than pyothorax, cytology of effusions do not typically show bacteria. This does not aid in the diagnosis but may help to rule out pyothorax. Protein content of the effusion is not helpful due to the interference of the refractive index by the high lipid content of the fluid.

Question 71

A 7-month old female spayed Persian presents for multifocal non-pruritic patchy alopecia with scaling. Skin scrapes and cytology have no significant findings. You suspect ringworm and perform a fungal culture using a DTM (dermatophyte test medium) culture plate. The culture plate turns red in one week. What is the next appropriate step?

Answer 71

Microscopic examination of culture material

Question 72

You are called over to a beef ranch to evaluate a herd with a history of diarrhea, reproductive problems, and occasional cerebellar hypoplasia. You suspect an underlying infection with bovine viral diarrhea. How is this virus most likely being maintained in the herd?

Answer 72

Persistently-infected carrier cattle that were infected as fetuses

Question 73

Treatment of stringhalt in a horse involves which of the following?

Answer 73

Tenectomy of the lateral digital extensor

Question 74

A 12-year old male neutered Terrier mix presents for a geriatric exam. Physical exam reveals mildly prominent mandibular, prescapular, and popliteal lymph nodes, and a prominent spleen. ``` CBC results: hematocrit of 35% (35-57%) reticulocytes 45,000/uL (0-100/uL) neutrophils 3,000/uL (2,900-12,000/uL) lymphocytes 40,000/uL (400-2,900/uL) monocytes 900/uL (100-1,400/uL) eosinophils 200/uL (0-1,300/uL) platelets 120,000/uL (211,000-621,000/uL) ``` A bone marrow aspirate shows 40% small lymphocytes. A mandibular lymph node aspirate shows 90% small lymphocytes. What is the cause for these findings?

Answer 74

Chronic lymphocytic leukemia

Question 75

Which of the following diseases does NOT cause fetal loss in pigs?

Answer 75

Chronic erysipelas infection

Question 76

This radiograph is of a dog with a one month history of coughing. What is your diagnosis?

Answer 76

Lung mass

Question 77

"Bark-field" is a large corporation that is buying a previously independent local feline veterinary practice and will be gaining control of that practice. This is an example of which of the following?

Answer 77

Acquisition

Question 78

Intramuscular injections into the caudal aspect of the thigh muscles are most often associated with damage to which major nerve in the dog?

Answer 78

Sciatic

Question 79

You are asked to interview an applicant for a veterinary technician job at your clinic. Which of the following is an acceptable interview question for you to ask the applicant?

Answer 79

Do you have a high school diploma or equivalent?

Question 80

A 3-year old male castrated domestic short hair cat presents for crusting and pruritus around the face, neck, and ears. Which of the following should be least likely on your list of differential diagnoses?

Answer 80

Eosinophilic granuloma Eosinophilic granulomas or linear granulomas are usually linear in shape and pink-yellow in color. Typically, they don't crust and are not usually pruritic. Notoedres acariasis, insect bite hypersensitivity, and dermatophytosis more characteristically cause pruritis, crusting, and often affect the head, neck, and ears.

Question 81

Which of these control measures would be least effective for reducing Culicoides hypersensitivity in horses?

Answer 81

Antihistamines

Question 82

The image below is from an aspirate taken through the soft palate from a mass in the nose of an 8-year old male neutered Rhodesian Ridgeback dog. Choose the correct cell type of origin AND classification.

Answer 82

Epithelial origin; carcinoma

Question 83

A 5-year old gelding is presented for a nodular mass lesion on its lateral neck region. A biopsy of the regions reveals collagen degeneration and granulomatous inflammation with eosinophils. Which of the following is not a reasonable treatment option for this horse?

Answer 83

Chlorhexidine scrub and warm compressing

Question 84

You are doing a summer externship in South America and performing physical exams on a variety of animals. You are performing a fundic exam on the eye of a horse and note what appears to be a worm migrating through the conjunctiva (see image). Because of the location and appearance of this parasite, you suspect this is which of the following?

Answer 84

Thelazia

Question 85

A 12-week old female Rottweiler puppy arrives at your clinic with a 4 day history of lethargy, anorexia, vomiting, and diarrhea. On physical exam, the puppy is dehydrated and the temperature is 104.2F (40.1 C). What is your primary differential?

Answer 85

Canine parvovirus These clinical signs most closely correlate with parvo. One must piece together the signalment, history, and clinical findings. Usually a dog with a foreign body will not have diarrhea and a fever. Dogs infected with Giardia will not necessarily vomit. The duration and severity of clinical signs rule out dietary indiscretion. Canine corona virus may cause similar clinical signs, but it is less likely for a dog to have such severe clinical signs.

Question 86

You visit a cage layer operation where there is a complaint of decreased egg production in 45-week old white leghorn hens. Daily mortality numbers in the poultry house are normal. On examination you note that some of the birds are coughing/sneezing, along with decreased egg production, there is an increased percentage of eggs that have wrinkled shells. This combination of findings is most consistent with which of the following infections?

Answer 86

Infectious bronchitis

Question 87

A 9-month old male pitbull presents to you for hindlimb lameness that developed suddenly several days ago and has gotten worse. On your examination, the dog is painful on palpation of the left tibia. You take radiographs of the tibia which are shown below. Which of the following is the most appropriate treatment for the suspected condition?

Answer 87

Carprofen

Question 88

A swine herd with excellent biosecurity has experienced some abortions in new replacement gilts they purchased which are bred and gestating in an on off-site facility just for P1 females (parity segregation). You have diagnosed Leptospira pomona as the serovar responsible. Which of the following is the best course of action to effectively control this disease?

Answer 88

Cull replacement gilts (parity segregation farm) and vaccinate sows on main farm

Question 89

What bacteria are most commonly associated with ulcerative posthitis (pizzle rot) in rams?

Answer 89

Corynebacterium renale

Question 90

During routine surveillance of a rainbow trout hatchery, the younger fish are noted to be swimming in an erratic pattern. On closer evaluation, the fish seem to be deformed around the head and spine. One of these fish is sacrificed for necropsy, and diffuse necrosis of the cartilage and spores in the cartilage are observed. What is your diagnosis?

Answer 90

Whirling disease

Question 91

An 8-year old male tomcat presents for having a one week history of progressive lethargy, anorexia, occasional sneezing, conjunctivitis, and nasal discharge. On physical exam you see several ulcerations in the mouth. What is the most likely diagnosis?

Answer 91

Feline calicivirus

Question 92

You are examining a group of 20 yearling beef heifers in a late summer in Alberta, Canada that has been cooler and wetter than normal. The heifers have been experiencing poor growth and diarrhea. The farmer reports that the cows have developed a frequent, non-productive cough after exertion in the past week. You examine the cows and find their vital parameters to be within normal limits with the exception of several mildly tachypneic cows. There is no ocular or nasal discharge seen. You auscult occasional crackles in many of the cows. Fecal examination reveals Dictyocaulus viviparus L3 in three of six samples. You treat the cows with ivermectin and see cessation of coughing and diarrhea within a few days. Which of the following would be the best way to prevent this problem next year now that there is a known risk?

Answer 92

Persistent use of anthelmintics 2 to 3 times during the grazing season

Question 93

Several members of a recently shorn flock of sheep have developed abscesses in the mandibular, prescapular, parotid, and prefemoral lymph nodes. You lance an abscess and obtain some of the thick, white to greenish pus for culture. After growing on an agar plate for 48 hours you note that there are several small whitish-to-opaque colonies which can be easily pushed across the plate like a hockey puck. What is your diagnosis?

Answer 93

Corynebacterium pseudotuberculosis causes caseous lymphadenitis in sheep and goats. The clinical signs and culture results are classic for C. pseudotuberculosis (especially the hockey puck feature).

Question 94

Which of the following is the best way to find Giardia canis trophozoites?

Answer 94

Direct fecal smear

Question 95

A swine farmer has recently noticed that young pigs are growing poorly and seem to develop all sorts of minor disease problems. You do a postmortem on two of the worst and note subacute hepatic necrosis and fibrosis. Which of the following steps should you now pursue to make a diagnosis?

Answer 95

Analyze feed for aflatoxin Aflatoxins are one of the mycotoxins, and cause damage to hepatocytes. The clinical signs can be vague, but the lesions are fairly specific (although pyrrolizidine alkaloid toxicosis must also be considered).

Question 96

A 2-year old male neutered domestic shorthair named Cooper presents for 2-month history of coughing with occasional wheezing. He is mildly tachypneic when he is active per the owner's observation. Cooper lives inside only. Currently no tachypnea or labored breathing are appreciated. Heart and lungs auscult normally. Bloodwork is unremarkable other than a mild eosinophilia. Heartworm and fecal testing are negative. Chest radiographs reveal a mild interstitial pattern with diffuse bronchial wall thickening. Which diagnosis and therapy would be most appropriate?

Answer 96

Feline asthma, prednisolone

Question 97

A 3-year old, male castrated domestic short-hair cat is presented to you for hematuria, strangiuria, and pollakiuria of 3 days duration. The cat has no other historical medical problems. What is the most likely diagnosis?

Answer 97

Feline idiopathic cystitis (FIC) Also known as FLUTD or FUS, FIC is the most common cause of signs referable to the lower urinary tract in young, otherwise healthy cats. Psychological stressors and environmental factors play an important role in the pathophysiology of this disease. Less than 2% of otherwise healthy cats under the age of 10 with lower urinary tract signs have primary bacterial UTI. Bladder stones are possible, but not nearly as common as FIC. While TCC is the most common bladder cancer seen in cats, it is still rare, and chiefly occurs in geriatric cats. Fanconi syndrome is a proximal tubular disease (most often seen in Basenjis) that does not cause lower-tract signs.

Question 98

The 35 day post-partum recumbent dairy cow in this image has normal vital parameters, appetite, and milk production but has mucous and pus running from her vulva. Speculum exam shows this material exiting the cervix. Rectal exam shows that she has an involuting uterus and normal ovaries. Which of the following treatments should be administered to help treat this condition and have the fewest negative economic effects such as prolonged milk withdrawal?

Answer 98

Systemic ceftiofur

Question 99

It is the middle of summer, and located in a pasture with a marshy area, several cattle are found dead. The only clinical sign observed by an employee was red urine. You perform a necropsy on one of the affected animals and notice that urine is dark red and all body fluids are icteric and hemorrhagic. There is evidence of hemorrhage in the abomasum and reticulum. Finally, the liver has an anemic infarct near the portal vein. What are these animals infected with?

Answer 99

Clostridium hemolyticum (Cl novyi type D)

Question 100

Zinc toxicity from ingestion of pennies minted after 1983 can cause which of the following?

Answer 100

Hemolysis

Question 101

Which of the following statements regarding coccidiosis in chickens is true?

Answer 101

The causative agent is of the genus Eimeria The disease causes severe diarrhea, decreased production, and death. There are numerous species of Eimeria specific to certain regions of the intestinal tract. Diagnosis involves demonstration of oocysts in the feces. Treatment is based on anti-coccidial drugs.

Question 102

You want to give a 22 pound cat a 5 mg/kg dose of a drug. The drug comes as a 2.5% solution. How many milliliters should you give the cat?

Answer 102

Second, you must be able to convert a percent solution to mg/ml. A 2.5% solution is 25 mg/ml. This is hard for some students to remember. A memory tip is that a 100% solution would be 1 gram/ml. Therefore a 50% solution would be 500mg/ml, and a 5% solution would be 50 mg/ml. The math to solve this question is: 22 lbs x (1 kg/2.2 lbs) x 5mg/kg x (1ml/25mg) = 2 ml

Question 103

``` Interpret the following blood gas results from a 4 year old female spayed dog: Base excess= -8 (-5 to 0 mmol/L) Anion gap=18 (8-25 mmol/L) pH 7.30 (7.35-7.45) pCO2=29 (34-40 mmHg) ```

Answer 103

Metabolic Acidosis, Respiratory Alkalosis The normal base deficit/excess of a dog is about -5 to 0 mmol/L. This means that this dog has a base deficit and therefore a metabolic acidosis. Although this dog has a base deficit, she still has a normal anion gap (18-25 mmol/L). There is a slight acidemia as normal pH is approximately between 7.35-7.45. Finally, normal pCO2 is approximately 40. This dog is hyperventilating and blowing off CO2. In other words, she is blowing off acid; therefore she has respiratory alkalosis. Causes of metabolic acidosis with a normal anion gap can include loss of bicarbonate due to diarrhea or vomiting.

Question 104

You are in a dairy performing pregnancy checks and notice white plaques on the vagina of the 27th cow that you rectal. What is your diagnosis?

Answer 104

Infectious pustular vulvovaginitis

Question 105

Which of these antibiotics is safest for use in guinea pigs?

Answer 105

Enrofloxacin

Question 106

A 7-year old male castrated cat presents for respiratory distress with open-mouth breathing. You initially place him in oxygen and obtain thoracic radiographs when he is stabilized. The films are shown here. What is your diagnosis?

Answer 106

Left-sided congestive heart failure The cardiac silhouette is tall suggestive of left ventricular enlargement and there is a diffuse unstructured interstitial pattern in the caudoventral and cranial lung fields. The pulmonary vasculature is also dilated. Remember that cats in heart failure can have edema distributed in patchy infiltrates throughout the lungs, in contrast to dogs where it is more typically in the perihilar region. Asthma is less likely as no clear bronchial markings are seen and because of the infiltrate. Neoplasia is a consideration, but doesn't explain the cardiac enlargement. Pneumonia could also cause this pattern of infiltrate (although it is more typically cranioventral), but also does not explain the cardiomegaly. There is no evidence of tracheal collapse, which is an exceedingly rare condition in the cat

Question 107

What is the hormonal profile of a female dog in estrus?

Answer 107

Falling estrogen, rising progesterone

Question 108

You have just been called to a small outdoor swine farm. The farmer just found what appear to be 3 different litters of aborted fetuses. The sows are roaming around the pasture and it is difficult to identify which animals have aborted (there are some pregnant and non-pregnant animals in the group). There are no noticeable respiratory signs on any of the sows either. The farmer is concerned the herd is undergoing an outbreak of porcine reproductive and respiratory syndrome (PRRS) virus. What should you do next?

Answer 108

Collect 6 aborted fetuses to test for PRRS virus via PCR Because the outbreak appears to be just beginning, you are more likely to find the actual virus on any sample tested rather than antibodies. It takes 10 - 14 days after exposure for antibodies to be detected. Research has shown that during a PRRS abortion outbreak, approximately 50% of aborted fetuses will test positive for virus (i.e. 50% chance of detection). Entire fetuses or just thoracic fluid are appropriate samples for submission. By including 6 aborted fetuses you will have a 98.5% chance of finding the virus if it is there. At the start of an outbreak, disease prevalence will be very low and therefore a very large sampling size would be needed to find a single positive animal.

Question 109

A 2-year old Thoroughbred race horse presents for lameness evaluation. The trainer reports that the lameness has been slowly progressive over the past 3 weeks. You observe the horse walk and see a short, choppy gait in the front legs. There is swelling over the front of both fetlock joints and palpation and flexion of the fetlocks elicits pain. Radiographs show no evidence of new bone formation in the fetlock. You diagnose the horse with osselets (periostitis of the distal dorsal cannon bone). What is the best treatment recommendation?

Answer 109

Rest, phenylbutazone, and intra-articular injections of sodium hyaluronate

Question 110

A 12-year old female spayed Lhasa Apso presents for her annual physical exam. The owners report that she is doing fine at home. Cardiac auscultation reveals a 2/6 left systolic murmur over the apex of the heart. Thoracic radiographs are within normal limits. Color Doppler echocardiography reveals a small regurgitant jet across a mildly thickened mitral valve. What should be recommended to the owner?

Answer 110

The dog probably has myxomatous mitral valve degeneration and does not need cardiac medications at this time, but she should be rechecked in several months. This disease commonly occurs in older dogs as a result of degeneration and accumulation of acid-staining mucopolysaccharides in the valves (most commonly the mitral valve). A dog with early stage changes does not need to be on cardiac medications. As the disease progresses and the heart chambers enlarge and the animal begins to show signs of heart failure, the dog should be placed on medications such as diuretics, ACE inhibitors, +/- pimobendan. Congenital mitral dysplasia would usually result in more marked cardiac changes (louder murmur, more regurgitation, dilated heart chambers) at a much earlier age. Myxomatous mitral valve degeneration patients do not need to be placed on antibiotics for fear of bacterial endocarditis. Patients with subaortic stenosis are placed on prophylactic antibiotics if put at risk for bacteremia.

Question 111

Several beef cows present with a history of decreased appetite and excessive salivation. On physical exam, their tongues are firm on palpation, nodular, and painful (see image). You diagnose actinobacillosis. What is your recommendation to the owner?

Answer 111

Change feed and treat Sodium iodide and antibiotics are effective. Given the presentation and clinical signs these animals have probably begun to ingest very rough and stemmed (scabrous) feed items which have injured their mouths. Upon injury, the normal inhabitant Actinobacillus lignieresii invades the soft tissues and causes the characteristic woody tongue granulomatous inflammation. These animals don't have rabies, and there is no need to cull them. Change feed before additional animals are affected. Do not use aminoglycosides as they have an extremely long withdrawal period.

Question 112

A 7-year old male intact Labrador Retriever presents for an increased respiratory effort. Chest radiographs were performed which were indicative of pleural effusion. Which of the following is the most reliable radiographic sign that would be indicative of pleural effusion?

Answer 112

Pleural fissure lines on both lateral and ventrodorsal projections Pleural fissure lines are typically diagnostic for pleural effusion. The fissures are the normal divides between the lung lobes and are not visualized on radiographs unless there is fluid in the chest or the pleura is very thickened. When there is a large amount of fluid, you may begin to appreciate a loss of detail, and it is possible lung lobes will collapse as a result of an inability to properly expand in the face of the pleural effusion. A lobar sign is seen when there is a line of demarcation between a radiopaque (normal) lung lobe and a radiodense (consolidated) lung lobe. There can be several causes for a lobar sign including hemorrhage, edema, or pus within the lobe. An air bronchogram is seen when alveolar edema occurs as a result of fluid accumulating within the alveoli. Alveolar edema will result in a sharp contrast between the fluid in the alveoli and the air in the bronchi.

Question 113

Which of these tests is most reliable in diagnosing a uterine infection in a mare?

Answer 113

Uterine cytology

Question 114

A client brings in her rabbit, which acutely went down in the hind limbs after playing with the owner's daughter yesterday. On physical exam, the rabbit is dribbling urine and has no withdrawal in the hind legs. Forelimbs are normal. What do you suspect?

Answer 114

Vertebral fracture

Question 115

A 1.5-year-old female Persian cat presents with dramatically enlarged mammary glands that the owner says have developed over several weeks. A brief ultrasound shows that the cat is not pregnant. What hormone is responsible for feline mammary hyperplasia (hypertrophy)?

Answer 115

Progesterone

Question 116

A 12-year-old female Scarlet Macaw from a large aviary presents for regurgitation, weight loss despite a good appetite, polyuria, and passage of undigested seeds in the feces. Which of the following is the most likely differential?

Answer 116

Proventricular dilatation syndrome

Question 117

An adult Amazon parrot presents to your clinic with a swollen, distended neck. It appears to be acting and breathing normally. On physical examination, you find that the skin of the neck is distended with air, the crop is empty, and the bird is non-painful. What is your diagnosis?

Answer 117

Ruptured cervical air sac The cervical air sac is part of the extensive respiratory system in birds, including the parrot. The air sac system extends into the region of the neck. When this air sac is ruptured, usually from a traumatic incident, air escapes from the air sacs and fill the subcutaneous space resulting in swelling of the neck. Aerophagia, PDD, and pneumothorax all would have accompanying clinical signs, and air dilation would not be evident in the coelomic cavity.

Question 118

Which of these is not indicated as the initial treatment of a suspected streptococcus equi ssp. equi infection, causing mandibular and retropharyngeal lymph node abscessation in a 2 year old horse?

Answer 118

Systemic penicillin When they have lymph node abscessation, antibiotics are contraindicated because they will prolong the course of the disease but will not eliminate it. Because this disease is spread by direct contact, isolation of the horse is important. To obtain a definitive diagnosis, the lymph nodes could be aspirated. The treatment is to lance abscesses ventrally and dispose of all the material from the abscess to prevent spread of the organism.

Question 119

A 10-year-old male Pomeranian presents to you with a 3-month history of wheezing and marked respiratory distress. The owner reports that he has been coughing sporadically as if trying to clear his throat of a hairball. The owner is a regular smoker. On your examination, the dog displays moderate expiratory difficulty. You submit blood work and take radiographs including inspiratory and expiratory lateral projections of the dog, which are shown below. Which of the following are commonly used to treat the likely condition?

Answer 119

Butorphanol and theophylline The radiographs show dynamic collapse of the intrathoracic trachea, carina, and mainstem bronchi. There is a marked redundant tracheal membrane in the cervical region. The left atrium may be slightly enlarged but there is no evidence of left heart failure. Based on these findings, you should suspect that tracheal collapse is the cause of the dog's clinical signs. Treatment options include bronchodilators (i.e. theophylline, terbutaline), cough suppressants (hydrocodone, butorphanol), weight loss, and corticosteroids to control inflammation. In severely affected dogs, sedation may be necessary to break the cough cycle. Dogs should be kept away from smoke and environmental pollution. About 70% of dogs respond to medical management. Those that don't are sometimes treated with stents or tracheal rings, but neither repairs the underlying cartilaginous defect. Furosemide is not an appropriate treatment as there is no evidence of heart failure. Nebulization and coupage are used to treat pneumonia, which is also not present in this case.

Question 120

You examine a cow with pruritic leg lesions consisting of papules, erythema, scaling, crusting, and alopecia (see image). Several animals in the herd have these same lesions. What should you do to make the diagnosis?

Answer 120

Skin scraping to identify chorioptic mites Treatment with ivermectin is usually effective. C. equi, C. ovis and C. capre are found respectively in horses, sheep and goats where they cause mange. Identifying the mite, along with lesion distribution, will determine which mange mite is responsible.

Question 121

While on a routine call for teeth floats, you notice that there is a significant amount of fiddleneck in the horse pasture. What are the histopathologic findings that are associated with consumption of this plant?

Answer 121

Megalocytosis, fibrosis, and biliary hyperplasia of the liver

Question 122

A 2-year old rabbit presents for scratching its ears. On physical exam you observe crusts and excoriations in its ears. Microscopic exam of the crusts reveals numerous mites. You prescribe ivermectin to treat which parasite in this rabbit?

Answer 122

Psoroptes cuniculi Psoroptes cuniculi, the rabbit ear mite, causes severe crusting and inflammation in the external ear canals. Treatment is ivermectin or selamectin. Encephalitozoon cuniculi is a microsporidian parasite of rabbits that causes neurologic and renal disease. Cheyletiella parasitovorax is the rabbit fur mite and causes white flakes that resemble dandruff. Otodectes cynotis is the ear mite of dogs and cats. Treponema paraluis cuniculi is the causative agent of rabbit syphilis.

Question 123

The dairy cow in the picture presents to you with mild signs of ataxia, a right eye droop, and right ear droop. Physical examination also reveals that she is also febrile and does not have a palpebral response on the right side. You are suspicious of Listeriosis and perform a CSF tap; you expect to find ________ on the cytology.

Answer 123

A mononuclear pleocytosis CSF tap is most important for distinguishing Listeriosis from thromboembolic meningoencephalitis (TEME), in which you will see a neutrophilic pleocytosis on CSF cytologic examination. Remember with Listeria, you will often observe CNS signs, an increased number of monocytes and macrophages. Also remember that Listeria is usually contracted from ingesting silage that has been stored at a pH > 5.0.

Question 124

Which of these is the primary means of heat dissipation for a rabbit?

Answer 124

Through the ears

Question 125

A horse gets into cow feed that contains the ionophore, monensin. What is your biggest concern?

Answer 125

Cardiotoxicity Monensin is a coccidiostat used to increase productivity in cattle. Horses are much more susceptible to toxic effects of monensin than cattle and mistakes in feeding or accidental access to cattle feed can lead to toxicity. Monensin toxicity results in myocardial necrosis and development of dilated cardiomyopathy in horses. Clinical signs include progressive respiratory distress, heart murmur, weakness, and hypovolemic shock. Acutely, mild colic and diarrhea can occur as well but is less of a concern than the cardiovascular effects.

Question 126

In mid-autumn you attend a group of 64 housed beef cattle aged 9-12 months, purchased from numerous markets over the previous 3 weeks. Frequent coughing has been heard in the group over the past week. The farmer has selected two inappetant animals with purulent ocular and nasal discharges for veterinary examination. Clinical examination reveals pyrexia 105.4 and 106.0F (40.8 to 41.1 C). The respiratory rate is increased and auscultation of the chest reveals referred upper respiratory tract noise. Visual inspection of the remainder of the group reveals a number of cattle with mucopurulent ocular and nasal discharges and tachypnea as well as several cows who have a swollen vulva with erosions and ulcers. Six animals are selected and examined, all of which have a rectal temperature > 105 F (40.6 C). What is the best way to confirm you presumptive diagnosis?

Answer 126

Viral isolation of nasal swab The case is strongly suggestive of infectious bovine rhinotracheitis (IBR) based on the clinical course. Diagnosis can be made from viral isolation of nasal or ocular swabs from live animals or from bronchial lymph nodes or tracheal tissue in deceased animals. Serology 2-3 weeks apart can also confirm a diagnosis of IBR. The different strains of IBR tend to produce different syndromes; in this case there are both respiratory and vaginal signs, a likely result of two or more strains being present since the calves recently came from multiple sources.

Question 127

At what day in gestation can pregnancy be first confirmed via ultrasound in cattle?

Answer 127

28 days

Question 128

In a flock of sheep, numerous animals develop crusting lesions around the coronary bands during a moist winter. As you remove the crusts, there is pink granulation tissue underlying the crusts. You perform cytology on one of the crusts and see branching "railroad tracks" of cocci bacteria. What are these bacteria?

Answer 128

Dermatophilus congolensis The disease described is commonly termed strawberry footrot. Dermatophilus can also cause rain scald, a similar crusting condition associated with moisture, and affecting the ears, muzzle, face, tail and sometimes the dorsum. It tends to affect younger animals more severely. The granulation tissue under the crusts gives the "strawberry" appearance, and the cocci in "railroad tracks" are the other key to the diagnosis. Staphylococcal dermatitis in sheep is usually due to S. aureus and is usually associated with a puncture or other injury to the skin, allowing invasion. Clostridium novyi in sheep and goats causes malignant edema or "bighead" which is a disease where clostridial spores enter through fighting wounds and cause head and neck edema. Dichelobacter nodosus is a cause of infectious footrot, which infects the claws of the feet.

Question 129

Bleeding abomasal ulcers (sometimes called type 2 ulcers) have been diagnosed in a 2-year old dairy cow with melena and anemia. Which of the following treatments is contraindicated?

Answer 129

Flunixin meglumine

Question 130

A 6 year old Saddlebred is presented for lethargy, anorexia and fever. Upon physical exam, you determine that the heart rate is approximately 90 beats/min. You quickly perform an ECG using the base-apex lead (see top image). What is the arrhythmia that you observe on the ECG (also consider what medication you would use to treat this arrhythmia)? (The bottom ECG strip is a normal rhythm for reference.)

Answer 130

Ventricular tachycardia

Question 131

Average gestation length in the mare is how long?

Answer 131

345 days

Question 132

A Paint horse mare gives birth to an all white foal (see image). What clinical sign would you expect to see in a foal with lethal white syndrome?

Answer 132

Constipation Lethal white foals have aganglionosis of the intestines which leads to hypomotility, megacolon, constipation, colic, and death.

Question 133

A 12-year old cat presents with an abnormal gait and appears to be walking with the both hocks dropped down low to the ground. The owner says the cat has been losing weight and drinking a lot of water. What diagnostic test should you run?

Answer 133

Blood glucose This cat is presenting with a plantigrade stance with the hocks dropped low to the ground. This finding is most often associated with a diabetic neuropathy. A blood glucose test is fast and inexpensive, and helps rule diabetes mellitus in or out. Additionally, a urinalysis to check for glucose and ketones would be appropriate. The urinalysis will be especially helpful when trying to differentiate between stress and diabetes. Most patients with stress hyperglycemia will not have glucose in the urine. Chronic unregulated diabetes often results in weight loss, polyuria and polydipsia, and can lead to this plantigrade stance. Chronic renal failure, which also causes weight loss and polyuria and polydipsia, does not cause the plantigrade stance. Cerebellar disease may result in ataxia, but the gait usually appears hypermetric or exaggerated and may have a sway to it. Echocardiogram would be an appropriate choice if you were suspicious of a saddle thrombus. This is a clot in the aorta, which typically blocks off blood flow at the inguinal region and results in cold hindlimbs and loss of femoral pulses. The thrombus may affect one or both limbs depending on its location. This is most often associated with underlying cardiac disease, and, in this condition, the cat usually presents with dragging one or both hindlimbs. You will be unable to feel a femoral pulse in the affected limb(s), and the affected limb(s) is/are often painful.

Question 134

Which of the following organisms has been associated with spirochaetal colitis in swine?

Answer 134

Brachyspira pilosicoli B. hyodysenteriae is the causative organism for swine dysentery. Lawsonia intracellularis causes ileitis. Trichuris suis is the porcine whipworm. Salmonella Typhimurium is associated with button ulcers in the colon.

Question 135

A 2-year old female spayed Dachshund presents for further evaluation as a result of a mass on the pinna noted by the owner. On physical exam, the only abnormality noted was this mass. Cytology is consistent with a histiocytoma. Which of the following is the most reasonable treatment option?

Answer 135

Benign Neglect

Question 136

A 7-year old male castrated Doberman presented for lethargy, anorexia, and a left forelimb lameness. He was started on meloxicam two days ago for neck pain and improved significantly, but he became very lethargic and inappetent last night and had a tarry stool. On physical exam, he had full range of motion in his neck, a hunched stance, conscious proprioceptive deficits in all feet, and his left forelimb was held in an abducted stance. He had a short choppy gait in his thoracic limbs and long lanky gait in his hind limbs. Hematochezia was noted on rectal palpation. Brief ultrasound did not show any evidence of pleural, pericardial, or abdominal effusion. The owners do not wish to pursue any diagnostics. What is your recommended treatment plan for the neurologic disease process you suspect?

Answer 136

Discontinue meloxicam. Start an oral opioid-based pain medication for 5 days. Then start an anti-inflammatory dose of a steroid. This dog has the classic two-engine gait characteristic of Wobbler's syndrome. The hematochezia noted on rectal exam, and the history of a tarry stool (suggesting upper GI bleeding) is likely due to the meloxicam which should be discontinued immediately. Medical management for Wobbler's syndrome involves an anti-inflammatory dose of a steroid. There is a three to five day wash out period needed after stopping meloxicam and before starting prednisone. Further diagnostics for Wobbler's syndrome involves imaging (cervical radiographs, myelogram, MRI or CT) and it can be helpful in ruling out neoplasia or traumatic injuries. The left forelimb lameness and abducted stance are likely due to a pinched nerve however further imaging would be needed for confirmation.

Question 137

Tularemia is an important zoonotic disease of certain wildlife and can transmit the disease to humans. What is the causative organism and most common natural wildlife host species?

Answer 137

Francisella tularensis, found in rabbits, hares and rodents

Question 138

What is the most appropriate maintenance fluid rate for a dog under anesthesia for routine abdominal surgery?

Answer 138

10 ml/kg/hr of lactated ringers

Question 139

A number of chickens in a flock have been dying acutely with dyspnea and mucoid discharge from the mouth and watery, whitish diarrhea in some birds. On postmortem, evaluation, you find vascular hyperemia of the abdominal organs. Which of the following findings would support a diagnosis of fowl cholera?

Answer 139

Gram negative bacteria in blood or tissues Fowl cholera is caused by Pasteurella multocida, a Gram negative, non motile, pleomorphic rod. As with most poultry diseases, it is preferable to prevent introduction of the disease into a flock with biosecurity measures. If treatment is attempted, it should ideally be based on culture and sensitivity but sulfonamides, tetracyclines, or penicillin are most often used. Intranuclear inclusion bodies from the tracheal epithelium are seen with Infectious Laryngotracheitis caused by a herpesvirus. Fowlpox virus produces intracytoplasmic inclusions. Liver necrosis with large, granular basophilic intracytoplasmic inclusions is consistent with avian chlamydiosis.

Question 140

Enzootic pneumonia and gangrenous mastitis in sheep (blue bag) can both be caused by _______.

Answer 140

Mannheimia hemolytica

Question 141

A 5-month-old Shih Tzu presents for greasy skin, pruritus, and mild hair loss of the face. You perform skin cytology and no bacteria or yeast are observed. What test, that is part of the minimum dermatological database, would you perform next?

Answer 141

Skin scrape Demodex injai typically causes greasy seborrhea, especially on the face and dorsal trunk. Terriers and Shih Tzus may be predisposed. Some dogs may be pruritic. This mite is long and slender when compared with Demodex canis. A diet trial and intradermal skin test may be indicated in the future if the skin scrape is negative. A bacterial culture may be needed if bacteria were seen on cytology. There is no indication to perform a CBC. None of the other tests would be considered part of a dermatological database.

Question 142

A herd of pigs is presented for various reasons; some pigs have been found suddenly dead with no other apparent clinical signs. Some animals are febrile, lethargic, unable to rise, and have multifocal diamond-shaped skin lesions over their bodies. Some animals have swollen, painful hocks and carpi. What is the most likely causative agent/diagnosis?

Answer 142

Erysipelothrix rhusiopathiae There are 3 forms of erysipelas. In the peracute form, pigs are found suddenly dead with no other clinical signs. In the acute form, the pigs become lethargic, painful in their joints, anorexic, and develop diamond-shaped skin lesions. In the chronic form, the arthritis progresses to the vertebral joints and the limb joints may fuse. All three forms of the disease can appear in a herd, particularly if there is noncompliance of vaccination of the herd and if treatment is delayed. The diamond-shaped skin lesions are pathognomonic for the disease.

Question 143

Employees in your veterinary clinic are discussing measures to prevent disease transmission between employees and between patients. One of them asks you if using Purell hand sanitizer will prevent transmission of most pathogens. You remember reading on the label that Purell is a 65% ethyl alcohol based antiseptic. Which of these agents would be most effectively killed by such a product?

Answer 143

Influenza virus

Question 144

Which of these drugs is used as a premedication prior to anesthesia to decrease salivary secretions, facilitating intubation in cats?

Answer 144

Atropine

Question 145

The syndrome of right dorsal colitis in horses is associated with which predisposing factor?

Answer 145

Administration of non-steroidal anti-inflammatory drugs (i.e. phenylbutazone)

Question 146

Which of the following statements is true about pinworm infections in mice?

Answer 146

Heavy parasite loads may lead to rectal prolapse

Question 147

Several of the young (6-10 week old) lambs in a flock have developed profuse watery diarrhea and anorexia with weight loss and dehydration. The fleece appears dull and coarse. On fecal evaluation, you detect many of the eggs shown in the image below (the egg is approximately 150 um long). Which of the following is an appropriate treatment?

Answer 147

Levamisole Nematodirus eggs have a characteristic elliptical appearance with sharply curved poles and 2-8 blastomeres surrounded by a wide fluid-filled cavity. Diagnosis can be difficult during the prepatent period when there may be little egg shedding. Levamisole is an imidazothiazole derivative that is effective against gastrointestinal roundworms and lungworms in sheep (Haemonchus, Trichostrongylus, Ostertagia, Cooperia, Nematodirus, Bunostomum, Oesophagostomum, Chabertia, Dictyocaulus. It is not effective against tapeworms and flukes. Commonly used sheep anthelmintics include albendazole, fenbendazole, ivermectin, levamisole, oxfendazole, and thiabendazole.

Question 148

A 3-year old female spayed indoor/outdoor domestic short hair presents for congestion and swelling over the bridge of the nose. The swelling over the nose is firm and seems to be subcutaneous. There is also mild enlargement of the mandibular lymph nodes. You perform cytology from a fine needle aspirate of the swelling over the nose and see narrow, budding, thin-walled yeasts surrounded by clear capsules (see picture). You also detected a lesion in the retina on fundic examination. Which of the following treatments would be indicated?

Answer 148

Itraconazole Based on the description of the cytology and clinical symptoms of this cat, the most likely diagnosis is Cryptococcus neoformans. This is a fungal disease that occurs when the organism is inhaled and is disseminated to skin, eyes, CNS, lungs, or other areas. The upper respiratory tract is most often involved and symptoms can include nasal discharge, sneezing, swelling over the nose, and regional lymphadenopathy. If the CNS is involved, seizures can also occur. The disease has been thought to be transmitted most often through infected pigeon droppings. Itraconazole or fluconazole are the anti-fungals of choice for this disease. Doxycycline, Trimethoprim sulfa, and Clavamox are all antibiotics and would not address a fungal infection. Lufenuron is a flea treatment that has had some implications for treatment of dermatophytes due to its ability to inhibit chitin. About 1/3 of the cell wall of a fungus is composed of chitin. This has not been a promising or approved treatment for ringworm and surely would not be an appropriate treatment for Cryptococcus.

Question 149

You are treating an 8-year old mix breed terrier for ventricular tachycardia post splenectomy. You determine that you've given too much lidocaine to the patient. What clinical signs or laboratory findings are you most likely to see initially?

Answer 149

Muscle tremors and seizures Early clinical signs associated with lidocaine toxicity include neurological symptoms such as seizures and tremors. Nausea and vomiting may occur, but is usually transient. Cardiovascular and respiratory depression can also occur, but usually later on in the course of clinical signs.

Question 150

What type of diet predisposes bucks to ulcerative posthitis?

Answer 150

The correct answer is high protein diet. When an animal is fed a high-protein diet, excess proteins are catabolized to urea and excreted. If urease-producing bacteria like Corynebacterium renale are present, the urea is broken down to ammonia in the prepuce, which causes damage to the mucosal surfaces and leads to pizzle rot.

Question 151

You are examining a 6-year old Thoroughbred gelding for acute onset of diarrhea on a warm summer day. Upon physical examination, tachycardia and fever are present along with severe diarrhea. You also notice signs of lameness in the front feet suggestive of laminitis. What is a cause of diarrhea that is seasonal and is associated commonly with laminitis?

Answer 151

Neorickettsia risticii (Potomac Horse Fever) Neorickettsia risticii commonly causes diarrhea in the warmer summer months and is observed in horses stabled near bodies of water. Although a trematode vector is suspected, the exact pathogenesis remains an area of study. The treatment is oxytetracycline. While many causes of diarrhea can result in laminitis, PHF has been associated with laminitis frequently. Salmonella can also result in the clinical signs noted but is not restricted by season.

Question 152

Water deprivation followed by unlimited access to water can cause which of the following signs in pigs?

Answer 152

The correct answer is head pressing. Water deprivation causes dehydration and an elevation in blood sodium concentration, which is one way sodium toxicity, or salt poisoning, can occur. When blood sodium concentration is elevated, the osmolarity of the blood increases and water from the brain diffuses into the vasculature. The brain responds by forming hyperosmolar particles to draw water back into the brain to prevent dehydration of its cells. Giving large amounts of free water in the form of drinking water or as a bolus of hyposmolar IV fluids will quickly drop the blood sodium concentration causing a large amount of water to diffuse into the brain cells due to preformed hyperosmolar particles. Cerebral edema then ensues and neurologic signs such as head pressing results. Treatment should be aimed at slowly decreasing blood sodium concentration by about 1 meq/hr to prevent cerebral edema. Pigs showing clinical signs of brain disease usually die despite treatment.

Question 153

Aural hematomas in pigs are often caused by which of the following?

Answer 153

Bites inflicted by other pen mates